Multicolor cinematograph and other films



Patented Jan. 29, 1929.

' UNITED STATES JOHN EDWARD THORNTON, OF LONDON, ENGLAND.

MULTIGOLOR'CINEMATOGRAPH AND OTHER FILMS.

Application mea May 5, 1924, serial no.

This invention relates to the production of transparent multi-color cinematograph film'- positives in Yfour or three colors or tones o color.`

In my application, Serial No. 711,251, I have described a`"multi-color cinematograph or other film-positive built up from four component images, each representing a section of four-image picture comprising either four or lo three colors, as desired, two lof the component images being formed upon one thin film and the other two upon another thin film, the two films preferably beingobtained by longitudinally severing a double-Width film upon which-two pairs of images have been formed side by side.

This invention relates to such a film produced by photo-mechanical printing of the several component-images upon non-sensitized surface (as distinct from the ordinary photographic printing on sensitized layers) and in the preparation of the face of the film to receive, hold and absorb such printing.

The invention is applicable to non-cinematograph-lms for use as lantern slides, window transparencies or the like.

The invention will be fully described with reference to the accompanying drawings,

wherein:

filFig. 1 is a perspective view of the finished Fig. 2 is a plan of thin -celluloid film-material showing the several successive printings thereon in four colors.

Fig 3 is a plan view of thin 'celluloid filmmaterial showing the several successive printings thereon, one color being repeated.

Fig 4 is a diagrammatic sectional view showing colloidifaces cemented together.

Fig. 5 is a 4dia ammatic sectional view showing Celluloid lm-material cemented together, and

Fig. 6 is a diagrammatic sectional view showing colloid face cemented to celluloid film-material.

Each section-film is composed of two section-images in two different complementa colors; and each section-film comprises adi ferent group oftwo differently colored sectionimages,the two section-films being complementary to each-Rother.; and/the two images of one group on one film are reversed in .relation to those on t e other film, so that' when laid face to fae(all four section- 4,layers of trans by which the -is made comprising 'the two section prints 711,252, and in Great Britain February 15, 1924.

images shall superimpose or-,face the same way to form one complete picture; the whole set of two films with four images therefore constitu@ one completecolor-picturel series when the two films are correctly assembled and indissolubly united to make one ncomplete single-strip multi-layer lm.

Both pairs of prints are formed by print-` ing two of the color-component images upon a double-width strip of film, and then printing the second pair side by side, then longitudinally severing the film' to form two single-Widthstrips-af'ter printing.

In their separate states each thin sectionfilm consists of a strlp of transparent celluloid or other waterproof material having a prepared face upon which two sections of/a four-color picture are printed in superimposition. J

In its complete state the finished film consists of two such strips of thin film which have each been rinted photo-mechanically in two colors and then cemented image-face to image-face, so that they finally form one' single film, of compound-layer but otherwise standard form and thickness, having the complete four-color picture enclosed andA embedded within the body of the film, pro-f tected and sandwiched between two outer arent waterproof material elicate color-picture is proall possibility of 'being tected against scratched whilst being handled or during its passage through the projection machine. To secure the best results, together with an approximately com lete chromatic scale, four colors are required). These may for example be red, blue, yellow and grey;or red, blue, green and violet;`or crimson, yellow,

dark-blue and light-blue; or any other suitable combination of the primary colors; the

fourth darker color, suh as grey, violet, or

dark-blue, serving to emphasize the shadows of the picture and lengthen its tonal scale.

In the preferred form of the invention f or a four-color picture one two-color film-print section-pictures for example of, crimson and yellow and another'` two-color film-print comprising section-'picturesof blue and een. If the prints are carefully made in t e correct shades of color the picture resulting will, whenl viewed as a transparency, apparently 'contain the following eolors :cr1mson, yellow, blue and from combination of green by direct -`colors, and orange, blue-istrip or strips used for printing from, algreen, purple, brown, black and other shades` Athough m some of the printing processes delndlrectly by combination or overlap of two scribed a negative-image printing-clich is o1 more colors, so that in eii'ect there will be required, and for other processes a positiveoriginal four which still further lengthen the Lprintingg-clichs must be prepared to suit the color scale. A the particular printing process adopted.

When a three-color picture is required. Also in reproducing from the primary i which is usuallyfcomposed of red, blue, and negatives secondary images to form the printyellow), two ofthe colors, for eXamp'lered ing-clichs care must `be taken to'make one 75 and yellow, are printed upon one section-film group or set of printing-clichs face one way and the remaining color, blue in two diiierent and the other set the reverse way, so that shades upon the other section-film; or altelprints made therefrom will correctly assemnatively each film may contain one of the ble face to face. colors such as the red and blue and the third Any primary negatives or secondary print- 80 color such as the yellow may be duplicated ing-clichs that are not correctly arranged at upon bot-h films. the start can be reconstructed by reproduction The vabove is a broad outline ofthe nVeIlthrough cameras and reversing prisms in any tion and I will now give amore detailed dewell-known manner in order to secure negascription of the various sections or steps of tives of the correct type. l 85 the complete/process. j Y Section mage identifica-tion marks.-

Then separate single strips are used for' either. negatives or` positives or both, it is a It will be obvious that the original (0I` convenience to have identification numbers or Camera) I SeCtOnnegaVeS IIIUS hWe their marks printed on the blank edges of negative 90 C0101 ValueS'COI'eCtly balanced by the USB 0f sections and print sections to ensure correct Correct 00101 lteI'S When PhOtOglilPhIlg-tO printing and`l correct assembling afterwards.

The prz'niiarg/ (or camera) negatives;

produce the negatives.. Y l i The same rule is useful in a lesser degree even Any set of the original color-sect1@ negaif the double-width negative and positive tive (camera) images may be reversed in rela- Strips are use@ v 95 tion to another by the use of prisms when F., t Z

photographing, in order that the prints will 7 m ma @ma correctly face when brought together. For the lm base any suitable transparent These original (camera) section-negatives material may be used, but material such as may be obtained by any of the ValOuS knOWIl Celluloid, cellulose-acetate, or the like is prel0n arrangements of camera and optical systems,Y ferred because it is waterproof and relatively but the several section-images of the same pC-L almost inexpansible, It is preferably made ture should be made from exactly the same and printed in the double-width form, and standpoint, through one lens, the 'primary longitudinally severed after printing.

40 image bein split by prisms or other devices, One face of the lmV strip is suitably pre- 105 each lighteam being then filtered through pared to receive a photo-mechanically printseparate color filters before reaching the paned image. For some processes the surface of chromatic sensitive negative ilm, all as is the Celluloid film base ma be slightly sofwell known andunderstood." The original tened; for Others it may e finely toothed;

negatives may be formed for four-color in a and for others it may be provided with a very 110 four-way group upon one double-width llil; thin coating of a colloid such as gelatine or in two groups upon two double-Width films, 01' the like, and in that case the colloid itself may y in successive order upon one single-wiLlLhe toothed, or softened, or made slightly lilm; or upon four separate single-wi th "hydroscopic 59- ilms; or upon one four-width film; or in any The waterproof base is preferably made 115 other suitable way, the pairs of negatives beabout .O02 inch thick and the colloid coatlng ing re-grouped on reproduced negatives. The about .001 inch thick, making together a sec- I negatives maybe placed in staggered orde!` tion-film having a total thickness of about upon the film, or with gaps between each suc- .003 inch, and the two layers of diiiierent phys- 55. cessive picture, for either' the four or threeicalcharacteristics must be indissolubly 12o color class of negatives. Or the negatives united or amalgamated by thesubstratumand may be ma e upon screen-film, which 'simultameans known to those versed 1n the art of film neously records all colors at one exposure in manufacture. n s Y the area of one picture, upon a. single-width But for those, rinting processes which do 60 strip of film, the colors being separated subnot require the, m base to be faced with a 125 sequently into separate film negatives.. colloid the base' may be made .003 inch thick.

'The' t. .Mr d. M8 lAfter the twofprinted thin section-lilms n secon nega wei-0T Pm ,mg w have been indissolubly united image-face to 6 The term negative is also hereinbefore image-.face they form one .compound-layer 5 a larger number of colors or shades than the image printing-clich is required. Therefore 70 il used in the sense that itindicates the clichfilm a thickness ofvabout .006 inch.,v i

during manufacture If these section-films aie found to be too thin and frail to withstand the rough lhandling in the film printery during printing and finishing, the iilni may be strengthened by a temporary reinforcing strip of paper, to which the celluloid side is attached or upon which it is cast or formed during the process of manufacturing the film material. This can be effected by means of an intermediate'exceedingly thin layer of adhesive rubber between the paper backing and Celluloid, which will effectuallyhold the film during all the processes and yet allow of the zbacking being readily stripped away after the two thin films have been indissolubly united face-to-face.

The printing process.

There are various known printing processes which can be used either alone or in combination in carryingout the invention, but these are `all of one class and may be described under the general terms of transfer processes though the name they are commonly known by isphoto-mechanical or iinbibition processes They all comprise the same general principle, in which a printing plate, band, or belt, which I term a rinting clich, is so prepared with images ormed by photographic means as to be ca able of printing or transferring its image by mechanical means without\the aid' of light or sensitized film. Instead a non-sensitive film is used having its surface suitably prepared for receiving or absorbing colored stiff inks, or solutions of dyes, in/direct ratio to the varying lights, shadows and gradations ofthe images on the yprinting clich. The inks or coloring matter used must b'e of a kind to suit the particular printing process and type of clich adopted,

and must be capable of transferring from the clich to the lm by the application of pressure Contact.

The followingcomprise brief descriptions and names by which these several rocesses are known, all of wlich are suitable or printing multi-color films according to this iny and then freel Aapplication o 1 vention.

(A.) Processes iving half-tone images and requiring the app cation of inks compose'd of dyes of coloring matter suspended in greasy or spirit mediums, and capable of first attachiiig to the image portion of the clich transferring/to the film by the pressure contact only. Rhisef comprise h h1 e ie processes, suc asty 'c usinv stiff, thick, reasy inks of consis enlcy containing a proportion of boiled linseed oi i Intaglio' processes, such as photogravure, very thin liquid inks containing nickbenzene, or naptha groups;

vimages and requiring t Planographic processes, such as collotype and lithographie, using very-stiff fatty inks having no ailinity for water.

` Details of all three groups, showing their application to ci'nematographic films, will be 70 fei'ied to the film by the applicati-ion of pres- 85 sure and prolonged contact /until the melted colloid has set or united sufficiently to permit removal of the -ilni with the partially soliditied colored colloid attached to its surface. These comprise v Woodbui-ytype and Stannotype. Fulll details of both processes will be Afound in the technical literature of the art,

and brief details showing the application of the Woodburytype process to cinematograph films will be found in Thorntons Patent No. 5100/ l5.

(C) Processes givinglnon-grainy full-tone e application of inks composed of dyes or other soluble colors in the form of watery or alcoholic solutions used as inks. These are used in conjunction with a printing clich of absorbent colloid such asgelatine or the like, the colloidof which has been sensitized with either bichromate or silver sensitizng mediums, and after. printing by exposure to light istreated with developing or other solutions by which parts of the clich are rendered non-absorbent and the remainder left absorbent. These unaltered absorbent portions constitute the grainless image, and `when the solution of colored ink is applied it is absorbed by the absogient portions 'of the clich to the point of cmplete saturation and rejected b the non-ab- 1 sorbent portions. When the lm is placed) in contactv and pressure applied `for afpror longed period the colored ink is withdrawn from thelprinting clich and absorbed into the absorbent vgelatine or other colloid with 1 vwhich tlielm is coated. These processes J ai'e,known by the names Pinatype, hydrotype, dye-printing and imbibition.

They are well-known and are described in 1 various patent specifications and in the technical literature.

' Registration.

Accurateregistration and superposition of 15.

f the several color sections is secured by means ply the second color;

of accurate perforations in the correspond.- ing films-both negative and positive-and by perfectly-fitting registration pins.

i Shin/tage.-

Uniform shrinkage is secured by the exercise of special care in all the operations and by maintaining the same temperatures of all materials, drying rooms, or other sources of expansion and contraction.

Superz'mposed plantings. The two colors by twoprintings are super- -imposed oneupon the other upon the same As'scmbz'ng and completing. i Having completed each of the 'two-color thin section-positives, it now only remains to assemble and unite them face-to-face so that their images are completely enclosed.

. This is done by first coating the printed face of each strip with an exceedingly thin layer of adhesive material, then drying same, then' moistening same and, after correctly assembling and registering the two strips by their registering pins, applying pressure pictureby-picture and step-by-step until the vtwo ilms are indissolubly united and become as one, with their pictures inside and waterproof base or support layers outside, pro

vided lwith perforations for feeding the completed film through any standard projector. Fuller detailsof this operation are' described in-a concurrent application. v

Whatl claim as my invention and desire to protect by Letters Patent is A* multi-colorv positive cinematograph film comprising a double width transparent support divided into two longitudinally parallel portions, of which two partial images are photo-mechanically printed directly upon one portion in two diiierent colors and upon the other portion in two other different colors,

the support being severed longitudinally to -orm two halves which are superimposed and adhesvely secured together to form a fourcolor single width film transparency. y

lIn testimony whereof I have hereunto set iny hand. K

JOHN EDWARD THORNTON. 

